1. Field of the Invention
The present invention relates to sport equipment, especially to extreme sport equipment.
2. Description of the Prior Arts
Extreme sport is a good choice for someone who likes adventures and exciting sports. When doing the extreme sport, the player dives and accelerates to leap from the ground. Following that, the player falls at very high speed to the ground. During the extreme sport, the player experiences the thrill generated by the variations of the acceleration and the freefall. In order to leap and slide during the extreme sport, the player may get assistance with a platform.
Please refer to FIGS. 10 and 11; one of the conventional extendable jumping platform assemblies has two jumping platforms 50 and a connecting board 60. A sliding portion 51 on a top surface of each jumping platform 50 is a curved surface and the height of the sliding portion 51 varies from low to high. The jumping platform 50 forms a docking portion 52 at the higher end of the sliding portion 51. The two docking portions 52 of the two jumping platforms 50 face to each other. Two opposite sides of a top surface 61 of the connecting board 60 are two connecting portions 62, and the two connecting portions 62 are capable of being mounted on the two docking portions 52 of the two jumping platforms 50, thereby completing the installation of the conventional extendable jumping platform assembly. Precisely, each docking portion 52 forms two mounting grooves 521, and each connecting portion 62 forms two corresponding mounting tenons 621, so that the mounting tenons 621 can be mounted in the mounting grooves 521. When using the extendable jumping platform assembly, the player moves at a high speed toward one of the jumping platforms 50 of the conventional extendable jumping platform assembly with a skateboard, a bicycle, or skates. With the curved sliding portion 51 and the height variation of the sliding portion 51, the player can slide or leap on one of the jumping platforms 50, and then back to the ground by the other jumping platform 50. During this process, the player can stay on the top surface 61 of the connecting board 60 and enjoy the admiration from spectators.
However, the shape of the conventional extendable jumping platform assembly is regular and uniform so that the conventional extendable jumping platform assembly can neither extend the lateral leaping range according to different usage demands, nor extend a length of the sliding portion 51 for changing leaping heights of the conventional extendable jumping platform assembly.
Then please refer to FIGS. 12 and 13. Another conventional extendable jumping platform assembly is installed by two juxtaposed jumping platforms 70 to increase a lateral leaping range. A top surface of each jumping platform 70 is a sliding portion 71, and the highest end of the sliding portion 71 is a jumping end 711. One lateral surface of the jumping platform 70 forms a plurality of mounting grooves 72 spaced from each other, and the other lateral surface of the jumping platform 70 forms a plurality of mounting tenons 73 spaced from each other; besides, the mounting tenons 73 are corresponding to the mounting grooves 72 in location. During installation, the mounting tenons 73 of one jumping platform 70 are mounted in the mounting grooves 72 of the other jumping platform 70, so that juxtaposition of the two jumping platforms 70 is accomplished.
Please also refer to FIGS. 14 and 15. The jumping platform 70 further forms a plurality of lapping grooves 74 spaced from each other on an end surface of the jumping platform 70, which allows the jumping platform 70 to assemble with a first extending platform 80 and a second extending platform 90 for extending the sliding length and changing the leaping height of the conventional extendable jumping platform assembly. The first extending platform 80 has a first base portion 81 on the bottom surface thereof and a sliding portion 82 on the top surface thereof. A lower end of the sliding portion 82 is a guiding end 821 and the higher end of the sliding portion 82 is a jumping end 822. An end surface of the first extending platform 80 corresponding to the jumping end 822 forms a plurality of lapping grooves 84, and the other end surface of the first extending platform 80 corresponding to the guiding end 821 forms a plurality of lapping tenons 83. The lapping tenons 83 can be mounted in the lapping grooves 74 of the jumping platform 70, which causes the jumping end 711 of the jumping platform 70 to connect the guiding end 821 of the first extending platform 80. The second extending platform 90 has a second base portion 91, a sliding portion 92, and a plurality of lapping tenons 93. The sliding portion 92 has a guiding end 921 and a jumping end 922. The structures of the second extending platform 90 and the first extending platform 80 are almost the same, but the differences between them are that the second base portion 91 is bigger than the first base portion 81, and the second extending platform 90 does not have any lapping groove. The lapping tenons 93 of the second extending platform 90 can be mounted in the lapping grooves 84 of the first extending platform 80, which causes the guiding end 921 of the second extending platform 90 to connect the jumping end 822 of the first extending platform 80.
However, after the two jumping platforms 70 are juxtaposed for extending the lateral leaping range, as shown in FIG. 12, the aforesaid another conventional extendable jumping platform assembly forms an obvious serrated joint seam 700 between the two jumping platforms 70. Therefore, when the player moves at a high speed on a surface of the sliding portion 71 of the two jumping platforms 70, the serrated joint seam 700 may make wheels of the skateboard, bicycle, or skates shake in instability, causing safety hazards. Besides, to extent the sliding length, heights of the additional first extending platform 80 and second extending platform 90 have to correspond to the leaping height of the conventional extendable jumping platform assembly. In other words, the height of the first base portion 81 and the second base portion 91 must be increased, and the volumes of the first base portion 81 and the second base portion 91 are also increased, which increases the costs of material and molding of the first extending platform 80 and the second extending platform 90, too. Furthermore, because of the increased volumes of the first base portion 81 and the second base portion 91, the cost of packaging is increased as well.
To overcome the shortcomings, the present invention provides an extendable jumping platform assembly to mitigate or obviate the aforementioned problems.